Alan Rossner - Academia.edu (original) (raw)

Papers by Alan Rossner

Environmental Science & Technology, Aug 4, 2015

Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f... more Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f commercial and consumer products. The leaching of BPA c a n r e s u l t i n human exposure via inhalation, ingestion, and dermal routes. As a result, humans have been exposed in their home and work environment to BPA. Conventional methods for BPA exposure assessment rely on cumbersome laboratory instrumentation with high capital and operational expenditures which limit the number of samples that can be analyzed. We report here the design of a compact portable colorimetric paper based biosensing device with integrated sampling/analysis units for field-based measurements of BPA in indoor dust. The system employs interchangeable low cost paper based enzyme sensors as a test zone for BPA detection interfaced with an air sampling cassette as a sample collection area. The sensor response was concentration dependent with a detection limit of 0.28 µg/g. The sensor was validated with the conventional Gas Chromatography (GC) method and used to detect BPA exposure in household dust. BPA concentrations ranged from 0.05 to 3.87 µg/g in 57 household dust samples when both methods were used. The potential of this method for field measurements of dust samples is discussed.

12th International Conference on Indoor Air Quality and Climate 2011, 2011

Annals of Work Exposures and Health, Feb 12, 2020

Objectives Talc is mined and milled throughout the world for use in a variety of industrial and c... more Objectives Talc is mined and milled throughout the world for use in a variety of industrial and consumer products. Although prior studies have evaluated workplace exposures or health effects from talc operations, the primary emphasis of these investigations has been on certain mineral contaminants (e.g. crystalline silica and asbestos) rather than talc itself. The purpose of this analysis is to evaluate historical worker exposures to respirable dust (as a measure of talc exposures) in the Vermont talc mines and mills, which involved a relatively pure form of talc (i.e. no asbestos and <0.25% or <1% crystalline silica). Methods Respirable dust sampling data collected for workers in the Vermont mines and mills, which have not been previously published, were obtained from both mining company records and Mine Safety and Health Administration (MSHA) inspections. Because of differences in sampling design, the company and MSHA data were analyzed and reported separately. Overall, nearly 700 respirable dust samples collected for 44 job categories at 7 site locations over an approximate 30-year period were analyzed. Results Average respirable dust concentrations were found to exceed occupational exposure limits (OELs) in the United States and other countries for several job categories and site locations. Regardless of data source, the highest observed exposures were for mining jobs involving the operation of heavy equipment to break up, move, or load raw ore from the mines and milling or shipping jobs involving the crushing of raw ore, cleaning and drying of processed talc, and bagging and packaging of the final talc product. When analyzing the company data, the arithmetic mean respirable dust concentration was 2.73 mg m−3 for Muckerman at Hammondsville Mine, 3.18 mg m−3 for dosco operator at Ludlow mines, 1.35 mg m−3 for crusher operator at Gassetts Mill, 2.4 mg m−3 for palletizer at West Windsor Mill, and 2.68 mg m−3 for bagging operator at Columbia Shipping Center. When analyzing the MSHA data, the arithmetic mean respirable dust concentration was 3.5 mg m−3 for kiln/dryer operator at Hammondsville Mine, 1.27 mg m−3 for driller at Ludlow mines, 3.69 mg m−3 for ball mill operator at Columbia mill, 3.02 mg m−3 for flotation operator at West Windsor Mill, and 3.24 mg m−3 for bagging operator at Columbia Shipping Center. Worker exposures were found to decline over time for many, but not all, jobs. Conclusions Our findings highlight potential high-risk jobs that might benefit from additional exposure control strategies at current or future talc manufacturing sites. The respirable dust measurements summarized here may also be used to reconstruct historical worker exposures at the Vermont sites or aid in subsequent epidemiology studies of this cohort focused on malignant or non-malignant respiratory disease.

Annals of Work Exposures and Health, Dec 25, 2017

Wood pellets are increasingly used for space heating in the United States and globally. Prior wor... more Wood pellets are increasingly used for space heating in the United States and globally. Prior work has shown that stored bulk wood pellets produce sufficient carbon monoxide (CO) to represent a health concern and exceed regulatory standards for occupational exposures. However, most of the pellets used for residential heating are sold in 40-pound (18.1 kg) plastic bags. This study measured CO emission factors from fresh, bagged-wood pellets as a function of temperature and relative humidity. CO concentrations increased with increasing temperature and moisture in the container. CO measurements in a pellet mill warehouse with stored pallets of bagged pellets had 8-h average CO concentrations up to 100 ppm exceeding occupational standards for worker exposure. Thus, manufacturers, distributors, and home owners should be aware of the potential for CO in storage areas and design facilities with appropriate ventilation and CO sensors.

Journal of the Air & Waste Management Association, May 1, 2008

It is well known that characterization of airborne bioaerosols in indoor environments is a challe... more It is well known that characterization of airborne bioaerosols in indoor environments is a challenge because of inherent irregularity in concentrations, which are influenced by many environmental factors. The primary aim of this study was to quantify the day-to-day variability of airborne fungal levels in a single residential environment over multiple seasons. Indoor air quality practitioners must recognize the inherent variability in airborne bio-aerosol measurements during data analysis of mold investigations. Changes in airborne fungi due to varying season and day is important to recognize when considering health impacts of these contaminants and when establishing effective controls. Using an Andersen N6 impactor, indoor and outdoor bioaerosol samples were collected on malt extract agar plates for 18 weekdays and 19 weekdays in winter and summer, respectively. Interday and intraday variability for the bioaerosols were determined for each sampler. Average fungal concentrations were 26 times higher during the summer months. Day-to-day fungal samples showed a relatively high inconsistency suggesting airborne fungal levels are very episodic and are influenced by several environmental factors. Summer bio-aerosol variability ranged from 7 to 36% and winter variability from 24 to 212%; these should be incorporated into results of indoor mold investigations. The second objective was to observe the relationship between biological and nonbiological particulate matter (PM). No correlation was observed between biological and nonbiological PM. Six side-by-side particulate samplers collected coarse PM (PM10) and fine PM (PM2.5) levels in both seasons. PM2.5 particulate concentrations were found to be statistically higher during summer months. Interday variability observed during this study suggests that indoor air quality practitioners must adjust their exposure assessment strategies to reflect the temporal variability in bioaerosol concentrations.

Atmospheric Environment, Aug 1, 2013

h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives.... more h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives. Sea salt, table salt and black pepper reduced the particle number emission rates. Tumeric and garlic powder had no effect on particle emissions from the heated oil.

ISEE Conference Abstracts, 2013

Journal of Emergency Management, 2010

Direct-reading organic vapor monitors (DROVMs) are widely used by industrial hygienists and emerg... more Direct-reading organic vapor monitors (DROVMs) are widely used by industrial hygienists and emergency responders as survey tools for the assessment of volatile organic compounds (VOCs) in occupational or emergency response settings. Although these monitors provide real-time information for expedient decision making, their utility in determining compliance with specific exposure limits is not well established. In addition, other VOCs that may be present in the same environment can act as interferents and adversely affect performance. This study assessed the effect of an interferent (hexane) on the performance of two representative commercially available monitors when measuring cyclohexane. The instrument readings were compared with concentrations measured with sorbent tubes, a standard compliance monitoring technique. Infrared-based concentration measurements were more precise at the two middle challenge concentrations (144 and 289 ppm), indicating a shift in instrument precision at ...

Environmental Science & Technology, 2015

Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f... more Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f commercial and consumer products. The leaching of BPA c a n r e s u l t i n human exposure via inhalation, ingestion, and dermal routes. As a result, humans have been exposed in their home and work environment to BPA. Conventional methods for BPA exposure assessment rely on cumbersome laboratory instrumentation with high capital and operational expenditures which limit the number of samples that can be analyzed. We report here the design of a compact portable colorimetric paper based biosensing device with integrated sampling/analysis units for field-based measurements of BPA in indoor dust. The system employs interchangeable low cost paper based enzyme sensors as a test zone for BPA detection interfaced with an air sampling cassette as a sample collection area. The sensor response was concentration dependent with a detection limit of 0.28 µg/g. The sensor was validated with the conventional Gas Chromatography (GC) method and used to detect BPA exposure in household dust. BPA concentrations ranged from 0.05 to 3.87 µg/g in 57 household dust samples when both methods were used. The potential of this method for field measurements of dust samples is discussed.

Epidemiology, 2006

Diesel exhaust has been associated with health effects in humans, including respiratory illness a... more Diesel exhaust has been associated with health effects in humans, including respiratory illness and cancer. Children are of particular concern regarding diesel exposure from schools buses because their lungs are still developing and they can be more susceptible to health ...

Journal of the Air & Waste Management Association, 2008

Traditional and modern techniques for bioaerosol enumeration were used to evaluate the relative e... more Traditional and modern techniques for bioaerosol enumeration were used to evaluate the relative efficiency of gaseous chlorine dioxide (ClO2) in reducing the indoor microbial contamination under field and laboratory conditions. The field study was performed in a highly microbially contaminated house, which had had an undetected roof leak for an extended period of time and exhibited large areas of visible microbial growth. Air concentrations of culturable fungi and bacteria, total fungi determined by microscopic count and polymerase chain reaction (PCR) assays, endotoxin, and (1 --> 3)-beta-D-glucan were determined before and after the house was tented and treated with ClO2. The laboratory study was designed to evaluate the efficiency of ClO2 treatment against known concentrations of spores of Aspergillus versicolor and Stachybotrys chartarum on filter paper (surrogate for surface treatment). These species are commonly found in damp indoor environments and were detected in the field study. Upon analysis of the environmental data from the treated house, it was found that the culturable bacteria and fungi as well as total count of fungi (as determined by microscopic count and PCR) were decreased at least 85% after the ClO2 application. However, microscopic analyses of tape samples collected from surfaces after treatment showed that the fungal structures were still present on surfaces. There was no statistically significant change in airborne endotoxin and (1 --> 3)-beta-D-glucan concentration in the field study. The laboratory study supported these results and showed a nonsignificant increase in the concentration of (1 --> 3)-beta-D-glucan after ClO2 treatment.

Environmental Science Technology, 2002

ABSTRACT Year-long measurements of particle size distributions (6 to 400 nm) at three levels over... more ABSTRACT Year-long measurements of particle size distributions (6 to 400 nm) at three levels over and in a Midwestern deciduous forest from two Scanning Mobility Particle Sizers (SMPS) and one Fast Mobility Particle Sizer (FMPS) indicate a high frequency with which ultra-fine particles are observed. Approximately 1 in 5 days exhibit class A nucleation events according to the University of Helsinki classification. Highest frequency of nucleation events are observed in spring (subsequent to leaf-on) but nucleation is observed in all seasons. Lowest ultra-fine particle concentrations are uniformly observed in the trunk space, and during leaf-on highest concentrations always occur at the upper-most measurement height (46 m). However, during leaf-off frequently the highest concentrations of ultra-fines (6-30 nm) are observed close to the canopy level (at 34 m above the canopy which extends to about 28-30 m). This situation, of highest concentrations being observed closest to the canopy, is nearly uniformly the case for event days from mid-February through March (i.e. prior to bud-break in mid-April). It may be due to a reduction in canopy dry deposition of ultra-fines during the leaf-off period, but may also reflect the role of an apparently senescent canopy or under-storey in stabilizing recently nucleated particles or simulating the growth of sub-10 nm particles. We will present comparisons of the characteristics of these events, postulates for their source and analyses concerning the growth rates and removal of the resulting particles.

International Journal of Environmental Research and Public Health

This study evaluated the use of a long-term capillary flow controller paired with an evacuated ca... more This study evaluated the use of a long-term capillary flow controller paired with an evacuated canister for indoor air exposure monitoring in a vapor intrusion (VI) environment with trichloroethylene in comparison to the traditional method utilizing a diaphragm flow controller. Traditionally, air sampling with 6 L evacuated canisters equipped with diaphragm flow controllers has been best suited for 8 to 24 h samples. New advances in capillary flow controllers can extend sampling to up to 3 weeks by reducing flow rates to 0.1 milliliters min−1. During six 2 wk sampling events, conventional diaphragm flow controller canisters were used to collect 24 h samples simultaneously with capillary flow controllers collecting 2 wk samples. Testing was performed at four indoor locations in buildings impacted by VI with co-located samples for each method at each location. All samples were analyzed using GC/MS, and the results were statistically analyzed to produce a direct comparison of the two s...

Synergist (Akron, Ohio), 2012

Assessing risk in the aggregate, cumulatively, and comparatively has entered a new era in which i... more Assessing risk in the aggregate, cumulatively, and comparatively has entered a new era in which innovative technologies and methods are allowing health science professionals to explore and solve ever more complex problems.1,2,3 Increasingly, risk assessments either support or are mandated by regulatory, management, business, and public policy decision making. They also support technical and lay educational efforts and behavior-based safety programs. Since the inception of our profession, industrial hygienists have been front and center in characterizing hazards and assessing exposures, which predates the four-step risk assessment paradigm articulated by the National Academy of Sciences (NAS) in its 1983 “Red Book”: hazard assessment, exposure assessment, dose-response assessment, and risk characterization. Many industrial hygienists have also participated in more recent initiatives, such as resource allocation, enterprise risk management, sustainability, and cost-benefit analysis.

Atmospheric Environment, 2013

h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives.... more h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives. Sea salt, table salt and black pepper reduced the particle number emission rates. Tumeric and garlic powder had no effect on particle emissions from the heated oil.

Air Quality, Atmosphere & Health, 2011

A community and personal exposure assessment was performed to evaluate the benzene concentrations... more A community and personal exposure assessment was performed to evaluate the benzene concentrations on the St. Regis Mohawk Tribe (SRMT) reservation at Akwesasne. The reservation is divided by the USA-Canada border. Located to the west of the reservation is a large aluminum smelter that routinely emits approximately 29,000 pounds of benzene per year. The objective of the campaign was to determine the benzene, toluene, ethyl benzene, and xylenes (BTEX) concentrations in ambient air on the reservation and characterize the benzene sources. These emissions, given the prevailing winds, could impact the SRMT community and may be a significant source of benzene on the reservation. However, the reservation has approximately 15 gas stations, a casino, and a major roadway (State Route 37) transecting it. Prior work has shown that traffic was the predominant source of benzene, and the smelter was not a significant contributor to airborne benzene. To asses exposure across the reservation, BTEX samples were collected at nine locations distributed across the reservation using 6-L stainless steel silonite canisters for 24 h every 6th day between May 2007 and July 2008. In addition, personal sampling using miniature canisters was conducted for 20 subjects selected from workers in the following microenvironments: restaurants, gas filling stations, solid waste collection, day care centers, casinos, offices (smoking and non-smoking) as well as vehicle repair shops. The samples were concentrated using a cryogenic preconcentrator and analyzed by GC/MS/FID. Moderate seasonal variability in BTEX concentrations was observed at all the sampling locations with fall and winter having higher concentrations than summer and spring. The sampling locations near busy roads and intersections had the highest BTEX concentrations. The highest BTEX personal exposures were observed at the gas stations and at the repair shop.

Journal of the Air & Waste Management Association, 2010

Concentrations of numerous ambient air pollutants have declined in recent years across the United... more Concentrations of numerous ambient air pollutants have declined in recent years across the United States. Although it can be expected that reductions in air pollutants are associated with reductions in health effects, it is unclear whether this is actually the case. The purpose of this analysis was to compare the levels of and relationships between air pollutants and acute respiratory outpatient visits for two consecutive time periods totaling 53 mo. Air pollution data were collected at a centrally located monitor in Atlanta, GA, and include 24-hr averages of particulate matter (PM) less than 2.5 m in aerodynamic diameter (PM 2.5) and its components; coarse PM (PM 10-2.5); PM less than 10 m in aerodynamic diameter (PM 10); oxygenated volatile organic compounds (OVOCs); 8-hr maximum ozone (O 3); and 1-hr maximum nitrogen dioxide (NO 2), carbon monoxide (CO), and sulfur dioxide (SO 2). In addition, several metals and fractions of elemental carbon (EC) and organic carbon (OC) were investigated. Daily outpatient visit data were obtained from the electronic data warehouse of the Atlanta-based region of a nonprofit managed care organization. Poisson general linear modeling determined associations between daily levels of acute visits for four diagnosis groups (adult and child asthma, upper and lower respiratory infection) and air pollution measurements. Overall declining trends were observed in air pollutants and acute visits over the study period. Childhood asthma had the greatest number of significant associations with air pollutants, namely zinc and EC. The significant lag time between pollutant measurement and visit occurrence changed from 3-5 days in the first time period to 6-8 days in the later time period, but there was general consistency in several childhood asthma and pollutant associations over both time periods. The greatest evidence for a reduction in pollution being associated with an improvement in health response was for lower respiratory disease visits, but even in this case changes in other factors that influence health responses make it difficult to demonstrate that changes in pollutant levels influence health outcomes. IMPLICATIONS Ambient air pollutant concentrations have declined across the United States, but it is unclear whether these reductions are associated with reductions in health effects. This analysis investigates the levels of and relationships between a host of air pollutants and acute respiratory illnesses for two consecutive time periods. Pollutants and visit rates generally declined, whereas associations between childhood asthma and zinc and EC were observed for both time periods. This consistency indicates potentially important PM components in the role of air pollution on childhood asthma. The analysis demonstrates the difficulty of evaluating health consequences of changes in air pollution.

Environmental Science & Technology, Aug 4, 2015

Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f... more Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f commercial and consumer products. The leaching of BPA c a n r e s u l t i n human exposure via inhalation, ingestion, and dermal routes. As a result, humans have been exposed in their home and work environment to BPA. Conventional methods for BPA exposure assessment rely on cumbersome laboratory instrumentation with high capital and operational expenditures which limit the number of samples that can be analyzed. We report here the design of a compact portable colorimetric paper based biosensing device with integrated sampling/analysis units for field-based measurements of BPA in indoor dust. The system employs interchangeable low cost paper based enzyme sensors as a test zone for BPA detection interfaced with an air sampling cassette as a sample collection area. The sensor response was concentration dependent with a detection limit of 0.28 µg/g. The sensor was validated with the conventional Gas Chromatography (GC) method and used to detect BPA exposure in household dust. BPA concentrations ranged from 0.05 to 3.87 µg/g in 57 household dust samples when both methods were used. The potential of this method for field measurements of dust samples is discussed.

12th International Conference on Indoor Air Quality and Climate 2011, 2011

Annals of Work Exposures and Health, Feb 12, 2020

Objectives Talc is mined and milled throughout the world for use in a variety of industrial and c... more Objectives Talc is mined and milled throughout the world for use in a variety of industrial and consumer products. Although prior studies have evaluated workplace exposures or health effects from talc operations, the primary emphasis of these investigations has been on certain mineral contaminants (e.g. crystalline silica and asbestos) rather than talc itself. The purpose of this analysis is to evaluate historical worker exposures to respirable dust (as a measure of talc exposures) in the Vermont talc mines and mills, which involved a relatively pure form of talc (i.e. no asbestos and <0.25% or <1% crystalline silica). Methods Respirable dust sampling data collected for workers in the Vermont mines and mills, which have not been previously published, were obtained from both mining company records and Mine Safety and Health Administration (MSHA) inspections. Because of differences in sampling design, the company and MSHA data were analyzed and reported separately. Overall, nearly 700 respirable dust samples collected for 44 job categories at 7 site locations over an approximate 30-year period were analyzed. Results Average respirable dust concentrations were found to exceed occupational exposure limits (OELs) in the United States and other countries for several job categories and site locations. Regardless of data source, the highest observed exposures were for mining jobs involving the operation of heavy equipment to break up, move, or load raw ore from the mines and milling or shipping jobs involving the crushing of raw ore, cleaning and drying of processed talc, and bagging and packaging of the final talc product. When analyzing the company data, the arithmetic mean respirable dust concentration was 2.73 mg m−3 for Muckerman at Hammondsville Mine, 3.18 mg m−3 for dosco operator at Ludlow mines, 1.35 mg m−3 for crusher operator at Gassetts Mill, 2.4 mg m−3 for palletizer at West Windsor Mill, and 2.68 mg m−3 for bagging operator at Columbia Shipping Center. When analyzing the MSHA data, the arithmetic mean respirable dust concentration was 3.5 mg m−3 for kiln/dryer operator at Hammondsville Mine, 1.27 mg m−3 for driller at Ludlow mines, 3.69 mg m−3 for ball mill operator at Columbia mill, 3.02 mg m−3 for flotation operator at West Windsor Mill, and 3.24 mg m−3 for bagging operator at Columbia Shipping Center. Worker exposures were found to decline over time for many, but not all, jobs. Conclusions Our findings highlight potential high-risk jobs that might benefit from additional exposure control strategies at current or future talc manufacturing sites. The respirable dust measurements summarized here may also be used to reconstruct historical worker exposures at the Vermont sites or aid in subsequent epidemiology studies of this cohort focused on malignant or non-malignant respiratory disease.

Annals of Work Exposures and Health, Dec 25, 2017

Wood pellets are increasingly used for space heating in the United States and globally. Prior wor... more Wood pellets are increasingly used for space heating in the United States and globally. Prior work has shown that stored bulk wood pellets produce sufficient carbon monoxide (CO) to represent a health concern and exceed regulatory standards for occupational exposures. However, most of the pellets used for residential heating are sold in 40-pound (18.1 kg) plastic bags. This study measured CO emission factors from fresh, bagged-wood pellets as a function of temperature and relative humidity. CO concentrations increased with increasing temperature and moisture in the container. CO measurements in a pellet mill warehouse with stored pallets of bagged pellets had 8-h average CO concentrations up to 100 ppm exceeding occupational standards for worker exposure. Thus, manufacturers, distributors, and home owners should be aware of the potential for CO in storage areas and design facilities with appropriate ventilation and CO sensors.

Journal of the Air & Waste Management Association, May 1, 2008

It is well known that characterization of airborne bioaerosols in indoor environments is a challe... more It is well known that characterization of airborne bioaerosols in indoor environments is a challenge because of inherent irregularity in concentrations, which are influenced by many environmental factors. The primary aim of this study was to quantify the day-to-day variability of airborne fungal levels in a single residential environment over multiple seasons. Indoor air quality practitioners must recognize the inherent variability in airborne bio-aerosol measurements during data analysis of mold investigations. Changes in airborne fungi due to varying season and day is important to recognize when considering health impacts of these contaminants and when establishing effective controls. Using an Andersen N6 impactor, indoor and outdoor bioaerosol samples were collected on malt extract agar plates for 18 weekdays and 19 weekdays in winter and summer, respectively. Interday and intraday variability for the bioaerosols were determined for each sampler. Average fungal concentrations were 26 times higher during the summer months. Day-to-day fungal samples showed a relatively high inconsistency suggesting airborne fungal levels are very episodic and are influenced by several environmental factors. Summer bio-aerosol variability ranged from 7 to 36% and winter variability from 24 to 212%; these should be incorporated into results of indoor mold investigations. The second objective was to observe the relationship between biological and nonbiological particulate matter (PM). No correlation was observed between biological and nonbiological PM. Six side-by-side particulate samplers collected coarse PM (PM10) and fine PM (PM2.5) levels in both seasons. PM2.5 particulate concentrations were found to be statistically higher during summer months. Interday variability observed during this study suggests that indoor air quality practitioners must adjust their exposure assessment strategies to reflect the temporal variability in bioaerosol concentrations.

Atmospheric Environment, Aug 1, 2013

h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives.... more h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives. Sea salt, table salt and black pepper reduced the particle number emission rates. Tumeric and garlic powder had no effect on particle emissions from the heated oil.

ISEE Conference Abstracts, 2013

Journal of Emergency Management, 2010

Direct-reading organic vapor monitors (DROVMs) are widely used by industrial hygienists and emerg... more Direct-reading organic vapor monitors (DROVMs) are widely used by industrial hygienists and emergency responders as survey tools for the assessment of volatile organic compounds (VOCs) in occupational or emergency response settings. Although these monitors provide real-time information for expedient decision making, their utility in determining compliance with specific exposure limits is not well established. In addition, other VOCs that may be present in the same environment can act as interferents and adversely affect performance. This study assessed the effect of an interferent (hexane) on the performance of two representative commercially available monitors when measuring cyclohexane. The instrument readings were compared with concentrations measured with sorbent tubes, a standard compliance monitoring technique. Infrared-based concentration measurements were more precise at the two middle challenge concentrations (144 and 289 ppm), indicating a shift in instrument precision at ...

Environmental Science & Technology, 2015

Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f... more Bisphenol A (BPA) is found in polycarbonate plastic and epoxy resins and is used in a variety o f commercial and consumer products. The leaching of BPA c a n r e s u l t i n human exposure via inhalation, ingestion, and dermal routes. As a result, humans have been exposed in their home and work environment to BPA. Conventional methods for BPA exposure assessment rely on cumbersome laboratory instrumentation with high capital and operational expenditures which limit the number of samples that can be analyzed. We report here the design of a compact portable colorimetric paper based biosensing device with integrated sampling/analysis units for field-based measurements of BPA in indoor dust. The system employs interchangeable low cost paper based enzyme sensors as a test zone for BPA detection interfaced with an air sampling cassette as a sample collection area. The sensor response was concentration dependent with a detection limit of 0.28 µg/g. The sensor was validated with the conventional Gas Chromatography (GC) method and used to detect BPA exposure in household dust. BPA concentrations ranged from 0.05 to 3.87 µg/g in 57 household dust samples when both methods were used. The potential of this method for field measurements of dust samples is discussed.

Epidemiology, 2006

Diesel exhaust has been associated with health effects in humans, including respiratory illness a... more Diesel exhaust has been associated with health effects in humans, including respiratory illness and cancer. Children are of particular concern regarding diesel exposure from schools buses because their lungs are still developing and they can be more susceptible to health ...

Journal of the Air & Waste Management Association, 2008

Traditional and modern techniques for bioaerosol enumeration were used to evaluate the relative e... more Traditional and modern techniques for bioaerosol enumeration were used to evaluate the relative efficiency of gaseous chlorine dioxide (ClO2) in reducing the indoor microbial contamination under field and laboratory conditions. The field study was performed in a highly microbially contaminated house, which had had an undetected roof leak for an extended period of time and exhibited large areas of visible microbial growth. Air concentrations of culturable fungi and bacteria, total fungi determined by microscopic count and polymerase chain reaction (PCR) assays, endotoxin, and (1 --> 3)-beta-D-glucan were determined before and after the house was tented and treated with ClO2. The laboratory study was designed to evaluate the efficiency of ClO2 treatment against known concentrations of spores of Aspergillus versicolor and Stachybotrys chartarum on filter paper (surrogate for surface treatment). These species are commonly found in damp indoor environments and were detected in the field study. Upon analysis of the environmental data from the treated house, it was found that the culturable bacteria and fungi as well as total count of fungi (as determined by microscopic count and PCR) were decreased at least 85% after the ClO2 application. However, microscopic analyses of tape samples collected from surfaces after treatment showed that the fungal structures were still present on surfaces. There was no statistically significant change in airborne endotoxin and (1 --> 3)-beta-D-glucan concentration in the field study. The laboratory study supported these results and showed a nonsignificant increase in the concentration of (1 --> 3)-beta-D-glucan after ClO2 treatment.

Environmental Science Technology, 2002

ABSTRACT Year-long measurements of particle size distributions (6 to 400 nm) at three levels over... more ABSTRACT Year-long measurements of particle size distributions (6 to 400 nm) at three levels over and in a Midwestern deciduous forest from two Scanning Mobility Particle Sizers (SMPS) and one Fast Mobility Particle Sizer (FMPS) indicate a high frequency with which ultra-fine particles are observed. Approximately 1 in 5 days exhibit class A nucleation events according to the University of Helsinki classification. Highest frequency of nucleation events are observed in spring (subsequent to leaf-on) but nucleation is observed in all seasons. Lowest ultra-fine particle concentrations are uniformly observed in the trunk space, and during leaf-on highest concentrations always occur at the upper-most measurement height (46 m). However, during leaf-off frequently the highest concentrations of ultra-fines (6-30 nm) are observed close to the canopy level (at 34 m above the canopy which extends to about 28-30 m). This situation, of highest concentrations being observed closest to the canopy, is nearly uniformly the case for event days from mid-February through March (i.e. prior to bud-break in mid-April). It may be due to a reduction in canopy dry deposition of ultra-fines during the leaf-off period, but may also reflect the role of an apparently senescent canopy or under-storey in stabilizing recently nucleated particles or simulating the growth of sub-10 nm particles. We will present comparisons of the characteristics of these events, postulates for their source and analyses concerning the growth rates and removal of the resulting particles.

International Journal of Environmental Research and Public Health

This study evaluated the use of a long-term capillary flow controller paired with an evacuated ca... more This study evaluated the use of a long-term capillary flow controller paired with an evacuated canister for indoor air exposure monitoring in a vapor intrusion (VI) environment with trichloroethylene in comparison to the traditional method utilizing a diaphragm flow controller. Traditionally, air sampling with 6 L evacuated canisters equipped with diaphragm flow controllers has been best suited for 8 to 24 h samples. New advances in capillary flow controllers can extend sampling to up to 3 weeks by reducing flow rates to 0.1 milliliters min−1. During six 2 wk sampling events, conventional diaphragm flow controller canisters were used to collect 24 h samples simultaneously with capillary flow controllers collecting 2 wk samples. Testing was performed at four indoor locations in buildings impacted by VI with co-located samples for each method at each location. All samples were analyzed using GC/MS, and the results were statistically analyzed to produce a direct comparison of the two s...

Synergist (Akron, Ohio), 2012

Assessing risk in the aggregate, cumulatively, and comparatively has entered a new era in which i... more Assessing risk in the aggregate, cumulatively, and comparatively has entered a new era in which innovative technologies and methods are allowing health science professionals to explore and solve ever more complex problems.1,2,3 Increasingly, risk assessments either support or are mandated by regulatory, management, business, and public policy decision making. They also support technical and lay educational efforts and behavior-based safety programs. Since the inception of our profession, industrial hygienists have been front and center in characterizing hazards and assessing exposures, which predates the four-step risk assessment paradigm articulated by the National Academy of Sciences (NAS) in its 1983 “Red Book”: hazard assessment, exposure assessment, dose-response assessment, and risk characterization. Many industrial hygienists have also participated in more recent initiatives, such as resource allocation, enterprise risk management, sustainability, and cost-benefit analysis.

Atmospheric Environment, 2013

h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives.... more h i g h l i g h t s Particle emissions were compared for cooking oils with and without additives. Sea salt, table salt and black pepper reduced the particle number emission rates. Tumeric and garlic powder had no effect on particle emissions from the heated oil.

Air Quality, Atmosphere & Health, 2011

A community and personal exposure assessment was performed to evaluate the benzene concentrations... more A community and personal exposure assessment was performed to evaluate the benzene concentrations on the St. Regis Mohawk Tribe (SRMT) reservation at Akwesasne. The reservation is divided by the USA-Canada border. Located to the west of the reservation is a large aluminum smelter that routinely emits approximately 29,000 pounds of benzene per year. The objective of the campaign was to determine the benzene, toluene, ethyl benzene, and xylenes (BTEX) concentrations in ambient air on the reservation and characterize the benzene sources. These emissions, given the prevailing winds, could impact the SRMT community and may be a significant source of benzene on the reservation. However, the reservation has approximately 15 gas stations, a casino, and a major roadway (State Route 37) transecting it. Prior work has shown that traffic was the predominant source of benzene, and the smelter was not a significant contributor to airborne benzene. To asses exposure across the reservation, BTEX samples were collected at nine locations distributed across the reservation using 6-L stainless steel silonite canisters for 24 h every 6th day between May 2007 and July 2008. In addition, personal sampling using miniature canisters was conducted for 20 subjects selected from workers in the following microenvironments: restaurants, gas filling stations, solid waste collection, day care centers, casinos, offices (smoking and non-smoking) as well as vehicle repair shops. The samples were concentrated using a cryogenic preconcentrator and analyzed by GC/MS/FID. Moderate seasonal variability in BTEX concentrations was observed at all the sampling locations with fall and winter having higher concentrations than summer and spring. The sampling locations near busy roads and intersections had the highest BTEX concentrations. The highest BTEX personal exposures were observed at the gas stations and at the repair shop.

Journal of the Air & Waste Management Association, 2010

Concentrations of numerous ambient air pollutants have declined in recent years across the United... more Concentrations of numerous ambient air pollutants have declined in recent years across the United States. Although it can be expected that reductions in air pollutants are associated with reductions in health effects, it is unclear whether this is actually the case. The purpose of this analysis was to compare the levels of and relationships between air pollutants and acute respiratory outpatient visits for two consecutive time periods totaling 53 mo. Air pollution data were collected at a centrally located monitor in Atlanta, GA, and include 24-hr averages of particulate matter (PM) less than 2.5 m in aerodynamic diameter (PM 2.5) and its components; coarse PM (PM 10-2.5); PM less than 10 m in aerodynamic diameter (PM 10); oxygenated volatile organic compounds (OVOCs); 8-hr maximum ozone (O 3); and 1-hr maximum nitrogen dioxide (NO 2), carbon monoxide (CO), and sulfur dioxide (SO 2). In addition, several metals and fractions of elemental carbon (EC) and organic carbon (OC) were investigated. Daily outpatient visit data were obtained from the electronic data warehouse of the Atlanta-based region of a nonprofit managed care organization. Poisson general linear modeling determined associations between daily levels of acute visits for four diagnosis groups (adult and child asthma, upper and lower respiratory infection) and air pollution measurements. Overall declining trends were observed in air pollutants and acute visits over the study period. Childhood asthma had the greatest number of significant associations with air pollutants, namely zinc and EC. The significant lag time between pollutant measurement and visit occurrence changed from 3-5 days in the first time period to 6-8 days in the later time period, but there was general consistency in several childhood asthma and pollutant associations over both time periods. The greatest evidence for a reduction in pollution being associated with an improvement in health response was for lower respiratory disease visits, but even in this case changes in other factors that influence health responses make it difficult to demonstrate that changes in pollutant levels influence health outcomes. IMPLICATIONS Ambient air pollutant concentrations have declined across the United States, but it is unclear whether these reductions are associated with reductions in health effects. This analysis investigates the levels of and relationships between a host of air pollutants and acute respiratory illnesses for two consecutive time periods. Pollutants and visit rates generally declined, whereas associations between childhood asthma and zinc and EC were observed for both time periods. This consistency indicates potentially important PM components in the role of air pollution on childhood asthma. The analysis demonstrates the difficulty of evaluating health consequences of changes in air pollution.